I am setting up a native plant garden in Seattle this fall. Since the plants I’m choosing are adapted to our dry summers, is it OK for my landscape to go without supplemental water next summer?
Expect that your new garden will still need some supplemental water next July and August. People often ask why it is necessary to water plants that can grow with just rainfall in the wild. Depending on the situation, though, it can be essential for several reasons. Our city gardens often have hot areas of paving nearby, and soil that’s compacted, sandy, or poor compared to forest or meadow soils. Wild plants spring up from seed or spread underground to where they can find water and other necessary conditions for their species, while the roots of transplants must suddenly support a whole plant in a new environment that is likely quite different than the native plant nursery where they were grown, and may also differ from the conditions for which they are ideally adapted. Climate change is a factor, too.
A great book that can help you with planning and maintaining landscapes with our native plants is April Pettinger and Brenda Constanzo’s Native Plants in the Coastal Garden. The authors emphasize the importance of siting your native plants well, in communities of plants that are suitable for the conditions you have. Their list of plants for dry places may be helpful to you if you are still choosing plants.